Cunning oil cooler plan..so fiendish...

**markm** · 27 Jun 08, 01:35 PM

I have a cunning plan, so fiendish m'lord.. well: I've been following Bohemian Georges "carbonworks" naca airducting on the nose job fairing doohdah with much interest and a few days ago gotto thinking that it would be good if the 2 air intakes on the noses of our bikes were actually put to some use rather than just being cosmetic doohdahs. At first i was thinking along the lines of getting air from up front from those intakes to the rear cylinder to help cool it, lets face it our engines run hot (very hot!) compared to others.. well...as per usual my train of thought went out on a tangent and i ditched the idea and came up with the cunning plan of adding an aditional oil cooler. So the flexi hose from my vaccum cleaner lives to fight anothr day..
Adrian K's solution (cant remember the post, but it had something to do with spaghetti headers) was neat and an inspiration. Anyway, i've a n oil cooler hanging around the garage (failed to sell on ebay) so i thought stuff it lets give it a go. No matter how i jiggled the bugger about i just didnt have the clearance to mount it nicely. So, this morning with time on my hands, whilst putting in new spark plugs and with lefthand fairing off, i had a brainwave

why not fit the damned cooler in the nose? I'll be damned it fits!!!!
I havent mounted it properly yet, but the plan will be to have it sort of rubber mounted (isolastic bushes, well nuts whatever).. a bit hard to explain in words but i have a mental image in my head of how its going to work. The plumbing and fittings will be mocked up at first using whatever tubing i've hanging around (bye bye garden hose!) and then whe i'm on my hols in july/aug have them made up proper..
Well guys... thats the plan. BUT before i start doing all this... your thoughts please? will it help cool the engine? Beneficial? yes? No? Any input greatly appreciated

mark

**lowry** · 27 Jun 08, 02:00 PM

if by any chance you dont go ahead with this, i'd be interested in the oil cooler, ive been after one for a while so if you dont use it in the end drop me a pm

**countcoupe** · 27 Jun 08, 02:00 PM

Hey Up,

Very interesting idea. Would the radiator not function aswell if it was to be turned through 90 degrees? Or am I missing something?

Count

**Ghost** · 27 Jun 08, 05:37 PM

It might fit in but its about as much use as an ashtray.

air will not go through the fins, path of least resistance and all that. Unless I'm missing something in the pic.

**Mr.R** · 27 Jun 08, 06:16 PM

Quote:

Originally Posted by Ghost

It might fit in but its about as much use as an ashtray.

air will not go through the fins, path of least resistance and all that. Unless I'm missing something in the pic.

Phil,
If you made up some sort of deflector/trunking from the two slots and sealed it down around the top of the cooler as it sits in the picture, leaving the bottom of the cooler open the air would have to go through it surely??
I had a similar set up in the nose of my 'Letterbox' Faired Rob North Trident, the cooler on that bike was enclosed in some kind of airbox with the only outlet being through the oilcooler and it worked fine.

Steve

**Ghost** · 27 Jun 08, 06:21 PM

Don't call me Shirley.

Yes with some dedicated cowling and deflecters it would work, but the hot air is then going to come out over the airbox and engines don't like sucking in hot air. So swings and roundabouts for a questionable gain. IMHO.

**geo7863** · 27 Jun 08, 06:21 PM

Mark I am fitting two oil coolers too, as my heads have been 'biggered' (yes bigger not bugger) out to 944, however I am putting one on the lower original mount, and one on the upper 'later' mount.

All that meant was getting a valve cover with the mounting sticky out bits for the upper mount, I am having the feed line go to the bottom cooler and then a vertical pipe joining the two coolers on t'other end and then the return from the upper cooler... or vice versa as I dont actually know which one is feed or return yet.

Your cooler in the nose job is what the old 900ss's had and the F1's, but they did have huge letterbox openings on them and I think smaller coolers than ours do.

Lowry old chap check out German and US ebay, some coolers come up remarkbly cheap, I got mine, almost brand spankers for $40...mind you some muppets try and sell them for over $300

**markm** · 27 Jun 08, 06:21 PM

Ah... Countcoupe and Ghost... to answer your question: well the photo dont exactly show how its going to be and its only just wedged in with some cardboard so that i could take a photo without the damned thing falling onto my mudguard. What the photo doesnt show is that the cooler at the moment is sitting at approx a 30 deg angle. When finally in there for good i'm aiming at approx 45 deg angle which i'm hoping will let air flow through it ok...and then theres cunning plan no.2 to be used in case there isnt adequate airflow and that involves making up a small scoop to divert the airflow straight through the cooler

BUT Guys: Are there any pro's and cons in adding an aditional oil cooler?

**Ghost** · 27 Jun 08, 06:28 PM

Yes in cold weather you won't need it and the oil could condensate a lot. But think about the hot air coming off it. If the air flow from the angled installation is good then with high ambients your engine will be having to suck in hot air which to a degree will degrade performance.

Only a dyno run would show how much tho'

**geo7863** · 27 Jun 08, 06:29 PM

Quote:

Originally Posted by markm

Ah... Countcoupe and Ghost... to answer your question: well the photo dont exactly show how its going to be and its only just wedged in with some cardboard so that i could take a photo without the damned thing falling onto my mudguard. What the photo doesnt show is that the cooler at the moment is sitting at approx a 30 deg angle. When finally in there for good i'm aiming at approx 45 deg angle which i'm hoping will let air flow through it ok...and then theres cunning plan no.2 to be used in case there isnt adequate airflow and that involves making up a small scoop to divert the airflow straight through the cooler

BUT Guys: Are there any pro's and cons in adding an aditional oil cooler?

Additional weight! overcooling when riding up in Northern Iceland!

**AdrianK** · 27 Jun 08, 07:13 PM

Fitting the extra cooler will (if correctly mounted) increase the cooling efficiency and also increase the oil capacity. I don't think running too cool is likely to be a problem unless you are planning a winter trip to Norway!

(I suppose if you were concerned you could always plumb in a bypass line).
However it is worth thinking about the siting of the additional cooler; is it reducing the airflow over the engine or even the rectifier? If so you might lose some or all of the potential advantages.
Have found my 944 runs significantly cooler but so far with no sign of the oil emulsifying.
A.

**geo7863** · 27 Jun 08, 07:30 PM

Quote:

Originally Posted by AdrianK

Fitting the extra cooler will (if correctly mounted) increase the cooling efficiency and also increase the oil capacity. I don't think running too cool is likely to be a problem unless you are planning a winter trip to Norway!

(I suppose if you were concerned you could always plumb in a bypass line).
However it is worth thinking about the siting of the additional cooler; is it reducing the airflow over the engine or even the rectifier? If so you might lose some or all of the potential advantages.
Have found my 944 runs significantly cooler but so far with no sign of the oil emulsifying.
A.

Thats why I have got the later fairings with the additional air deflector to the vertical cylinder, and as Mark pointed out am also making ducts from the small grilles at the front.

**zimbo** · 27 Jun 08, 07:32 PM

Also, had you considered why there are two slots in the fairing? Could it be that they are there to reduce a low presure buildup behind the fairing nosecone at speed, which may possibly affect airflow over the air intake or around the vertical cylinder, and that diverting or blocking this air stream may have adverse aerodynamic effects elsewhere?

I wouldn't consider a second oil cooler necessary at all unless you have done a lot of work on the engine (big bore, high compression, porting, carburation etc). Just my opinion, of course.

**Mr.R** · 27 Jun 08, 07:38 PM

Quote:

Originally Posted by Ghost

Don't call me Shirley.

Yes with some dedicated cowling and deflecters it would work, but the hot air is then going to come out over the airbox and engines don't like sucking in hot air. So swings and roundabouts for a questionable gain. IMHO.

Ah yes come to think about it Phil the hot air was ducted out of the sides of the fairing on the Rob North Letterbox via some hoover tubes.
I do have an oilcooler fitted under the nose of the top half fairing on my old bevel which works well, but it's facing the incoming air squarely, it hangs below the headlamp from the fairing bracket via some anti-vibe blocks.

Steve

**Mr.R** · 27 Jun 08, 07:59 PM

Quote:

Originally Posted by zimbo

Also, had you considered why there are two slots in the fairing? Could it be that they are there to reduce a low presure buildup behind the fairing nosecone at speed, which may possibly affect airflow over the air intake or around the vertical cylinder, and that diverting or blocking this air stream may have adverse aerodynamic effects elsewhere?

I wouldn't consider a second oil cooler necessary at all unless you have done a lot of work on the engine (big bore, high compression, porting, carburation etc). Just my opinion, of course.

Hi,
I might be wrong here but I've always thought that the two slots under the nose of the fairing were just a styling exercise??
They were just trying to make the bike look sporty.
At the time the 851's had two slots that were connected via hoses to the airbox and were winning WSB races, the earlier Pantah based racers had the oilcoolers fitted up in the nose behind a perforated section and later models had a slot in the lower nose.

Steve